1. Field of the Invention
The present invention relates to a recording apparatus for forming a visible image on a recording medium by receiving supply of image data, and a recording control method therefor.
2. Related Background Art
In a recording apparatus employing an ink jet recording head, formation of a visible image on a recording medium has been achieved by recording scanning operation, by reciprocating motion of the ink jet recording head on the recording medium. In particular, there has recently been developed an ink jet recording apparatus designed for recording on a large-sized recording medium such as wall paper. In such recording apparatus, a printing unit including an ink jet recording head is separated from a conveying unit for conveying the recording medium, and the printing operation is conducted by the combination of a reciprocating scanning operation of the recording head in the main scanning direction and transportation of the recording medium in the subscanning direction, through communication between the units.
The U.S. patent application Ser. No. 08/258,455 of the present applicant, filed on Jun. 10, 1994, discloses, in such recording apparatus in which the conveying unit for conveying the recording medium and the printing unit including the recording head are separated, to effect the recording operation by communication between the conveying unit and the printing unit through a predetermined communication protocol, and to achieve printing on a printing medium with a joint in such a manner that the recording head does not touch the joint portion.
In general, the recording head is mounted on a unit, called carriage, for supporting the recording head, and such carriage is connected to a driving device and moves the recording head in the scanning direction to achieve the recording operation. The driving device is so designed to drive the carriage with a speed matching the characteristics of the recording head. However, the driving device requires a certain time, depending on the characteristics thereof, to reach a predetermined speed from the stopped state or to reach the stopped state from the predetermined speed.
In the communication between the printing unit and the conveying unit in the above-explained conventional recording apparatus, a conveying request signal for the printing medium is sent from the printing unit to the conveying unit while the recording head is in the stopped position. The stopped position is so selected that the recording head is sufficiently distant, in the scanning direction, from the printing medium and does not hinder the conveying operation thereof. Also in the stopped position, the printing unit receives, from the conveying unit, a signal indicating the completion of conveying operation of the printing medium, and starts the scanning operation for next recording.
Although the time and the moving distance of the recording head, other than those required for the actual recording operation of the recording head, are unavoidable because of the characteristics of the driving device, it will be apparent that there can be realized a higher printing speed and a more dimension of the apparatus as such time and moving distance become smaller.